Development of Novel Mixed Halide/Superhalide Tin-Based Perovskites for Mesoscopic Carbon-Based Solar Cells.

Tin perovskites suffer from poor stability and a self-doping effect. To solve this problem, we synthesized novel tin perovskites based on superhalide with varied ratios of tetrafluoroborate to iodide and implemented them into solar cells based on a mesoscopic carbon-electrode architecture because film formation was an issue in applying this material for a planar heterojunction device structure. We undertook quantum-chemical calculations based on plane-wave density functional theory (DFT) methods and explored the structural and electronic properties of tin perovskites FASnI(BF) in the series = 0, 1, 2, and 3.

Mixed-Halide CH3 NH3 PbI3-x Xx (X=Cl, Br, I) Perovskites: Vapor-Assisted Solution Deposition and Application as Solar Cell Absorbers.

There have been recent reports on the formation of single-halide perovskites, CH3 NH3 PbX3 (X=Cl, Br, I), by means of vapor-assisted solution processing. Herein, the successful formation of mixed-halide perovskites (CH3 NH3 PbI3-x Xx ) by means of a vapor-assisted solution method at ambient atmosphere is reported. The perovskite films are synthesized by exposing PbI2 film to CH3 NH3 X (X=I, Br, or Cl) vapor.

A Three-Step Method for the Deposition of Large Cuboids of Organic-Inorganic Perovskite and Application in Solar Cells.

A three-step method for the deposition of CH3 NH3 PbI3 perovskite films with a high crystalline structure and large cuboid overlayer morphology is reported. The method includes PbI2 deposition, which is followed by dipping into a solution of C4 H9 NH3 I (BAI) and (BA)2 PbI4 perovskite formation. In the final step, the poorly thermodynamically stable (BA)2 PbI4 phase converts into the more stable CH3 NH3 PbI3 perovskite by dipping into a solution of CH3 NH3 I.